An antimony film electrode was prepared ex situ using a reversibly deposited mediator and applied to a model of metal ions (Hg(II)) by anodic stripping voltammetry. The electrochemical method for antimony film formation is based on a co-deposition of a metal of interest (Sb), with a reversibly deposited mediator (Cd), and then further on an oxidation of cadmium, with additional deposition of antimony by the appropriate potential. This serves to increase the density of concentrations of Sb atoms, promoting antimony film growth, and consequently helps to improve the electrochemical properties of the electrode. The structural and chemical information about antimony film electrodes prepared without and with a mediator were derived from data obtained via optical microscope, AFM and XPS analysis. Finally, the practical analytical application of the antimony film electrode (prepared with said mediator) was successfully tested by measuring the level of Hg(II) concentration in the certified reference material (1641d) and Vistula river water samples. (C) 2016 The Electrochemical Society. All rights reserved.